Total Complexity | 107 |
Total Lines | 878 |
Duplicated Lines | 0 % |
Changes | 1 | ||
Bugs | 0 | Features | 0 |
Complex classes like Crypt often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Crypt, and based on these observations, apply Extract Interface, too.
1 | <?php |
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81 | class Crypt implements CryptInterface |
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82 | { |
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83 | public const PADDING_ANSI_X_923 = 1; |
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84 | public const PADDING_DEFAULT = 0; |
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85 | public const PADDING_ISO_10126 = 3; |
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86 | public const PADDING_ISO_IEC_7816_4 = 4; |
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87 | public const PADDING_PKCS7 = 2; |
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88 | public const PADDING_SPACE = 6; |
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89 | public const PADDING_ZERO = 5; |
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90 | |||
91 | /** |
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92 | * @var string |
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93 | */ |
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94 | protected $authData = ""; |
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95 | |||
96 | /** |
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97 | * @var string |
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98 | */ |
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99 | protected $authTag; |
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100 | |||
101 | /** |
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102 | * @var int |
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103 | */ |
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104 | protected $authTagLength = 16; |
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105 | |||
106 | /** |
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107 | * Available cipher methods. |
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108 | * |
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109 | * @var array |
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110 | */ |
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111 | protected $availableCiphers; |
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112 | |||
113 | /** |
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114 | * @var string |
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115 | */ |
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116 | protected $cipher = "aes-256-cfb"; |
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117 | |||
118 | /** |
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119 | * The name of hashing algorithm. |
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120 | * |
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121 | * @var string |
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122 | */ |
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123 | protected $hashAlgo = "sha512"; |
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124 | |||
125 | /** |
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126 | * The cipher iv length. |
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127 | * |
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128 | * @var int |
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129 | */ |
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130 | protected $ivLength = 16; |
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131 | |||
132 | /** |
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133 | * @var string |
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134 | */ |
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135 | protected $key = ""; |
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136 | |||
137 | /** |
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138 | * @var int |
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139 | */ |
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140 | protected $padding = 0; |
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141 | |||
142 | /** |
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143 | * Whether calculating message digest enabled or not. |
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144 | * |
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145 | * @var bool |
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146 | */ |
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147 | protected $useSigning = true; |
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148 | |||
149 | /** |
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150 | * Crypt constructor. |
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151 | * |
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152 | * @param string $cipher |
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153 | * @param bool $useSigning |
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154 | * |
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155 | * @throws Exception |
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156 | */ |
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157 | public function __construct( |
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158 | string $cipher = "aes-256-cfb", |
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159 | bool $useSigning = false |
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160 | ) { |
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161 | $this->initializeAvailableCiphers(); |
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162 | |||
163 | $this->setCipher($cipher); |
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164 | $this->useSigning($useSigning); |
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165 | } |
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166 | |||
167 | /** |
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168 | * Decrypts an encrypted text. |
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169 | * |
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170 | * ```php |
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171 | * $encrypted = $crypt->decrypt( |
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172 | * $encrypted, |
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173 | * "T4\xb1\x8d\xa9\x98\x05\\\x8c\xbe\x1d\x07&[\x99\x18\xa4~Lc1\xbeW\xb3" |
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174 | * ); |
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175 | * ``` |
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176 | * |
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177 | * @param string $text |
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178 | * @param string|null $key |
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179 | * |
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180 | * @return string |
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181 | * @throws Exception |
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182 | */ |
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183 | public function decrypt(string $text, string $key = null): string |
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184 | { |
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185 | if (empty($key)) { |
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186 | $decryptKey = $this->key; |
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187 | } else { |
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188 | $decryptKey = $key; |
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189 | } |
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190 | |||
191 | if (empty($decryptKey)) { |
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192 | throw new Exception("Decryption key cannot be empty"); |
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193 | } |
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194 | |||
195 | $cipher = $this->cipher; |
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196 | $mode = strtolower( |
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197 | substr($cipher, strrpos($cipher, "-") - strlen($cipher)) |
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198 | ); |
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199 | $authData = $this->authData; |
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200 | $authTag = $this->authTag; |
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201 | |||
202 | $this->assertCipherIsAvailable($cipher); |
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203 | |||
204 | $ivLength = $this->ivLength; |
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205 | |||
206 | if ($ivLength > 0) { |
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207 | $blockSize = $ivLength; |
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208 | } else { |
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209 | $blockSize = $this->getIvLength( |
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210 | str_ireplace("-" . $mode, "", $cipher) |
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211 | ); |
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212 | } |
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213 | |||
214 | $iv = mb_substr($text, 0, $ivLength, "8bit"); |
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215 | |||
216 | if ($this->useSigning) { |
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217 | $hashAlgo = $this->getHashAlgo(); |
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218 | $hashLength = strlen(hash($hashAlgo, "", true)); |
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219 | $hash = mb_substr($text, $ivLength, $hashLength, "8bit"); |
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220 | $ciphertext = mb_substr($text, $ivLength + $hashLength, null, "8bit"); |
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221 | |||
222 | if ( |
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223 | ("-gcm" === $mode || "-ccm" === $mode) && |
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224 | !empty($this->authData) |
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225 | ) { |
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226 | $decrypted = openssl_decrypt( |
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227 | $ciphertext, |
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228 | $cipher, |
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229 | $decryptKey, |
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230 | OPENSSL_RAW_DATA, |
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231 | $iv, |
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232 | $authTag, |
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233 | $authData |
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234 | ); |
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235 | } else { |
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236 | $decrypted = openssl_decrypt( |
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237 | $ciphertext, |
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238 | $cipher, |
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239 | $decryptKey, |
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240 | OPENSSL_RAW_DATA, |
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241 | $iv |
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242 | ); |
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243 | } |
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244 | |||
245 | if ($mode == "-cbc" || $mode == "-ecb") { |
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246 | $decrypted = $this->cryptUnpadText( |
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247 | $decrypted, |
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248 | $mode, |
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249 | $blockSize, |
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250 | $this->padding |
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251 | ); |
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252 | } |
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253 | |||
254 | /** |
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255 | * Checks on the decrypted's message digest using the HMAC method. |
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256 | */ |
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257 | if (hash_hmac($hashAlgo, $decrypted, $decryptKey, true) !== $hash) { |
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258 | throw new MismatchException("Hash does not match."); |
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259 | } |
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260 | |||
261 | return $decrypted; |
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262 | } |
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263 | |||
264 | $ciphertext = mb_substr($text, $ivLength, null, "8bit"); |
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265 | |||
266 | if (("-gcm" === $mode || "-ccm" === $mode) && !empty($this->authData)) { |
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267 | $decrypted = openssl_decrypt( |
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268 | $ciphertext, |
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269 | $cipher, |
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270 | $decryptKey, |
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271 | OPENSSL_RAW_DATA, |
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272 | $iv, |
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273 | $authTag, |
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274 | $authData |
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275 | ); |
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276 | } else { |
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277 | $decrypted = openssl_decrypt( |
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278 | $ciphertext, |
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279 | $cipher, |
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280 | $decryptKey, |
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281 | OPENSSL_RAW_DATA, |
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282 | $iv |
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283 | ); |
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284 | } |
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285 | |||
286 | if ($mode == "-cbc" || $mode == "-ecb") { |
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287 | $decrypted = $this->cryptUnpadText( |
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288 | $decrypted, |
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289 | $mode, |
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290 | $blockSize, |
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291 | $this->padding |
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292 | ); |
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293 | } |
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294 | |||
295 | return $decrypted; |
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296 | } |
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297 | |||
298 | /** |
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299 | * Decrypt a text that is coded as a base64 string. |
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300 | * |
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301 | * @param string $text |
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302 | * @param null $key |
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303 | * @param bool $safe |
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304 | * |
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305 | * @return string |
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306 | * @throws Exception |
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307 | */ |
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308 | public function decryptBase64( |
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309 | string $text, |
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310 | $key = null, |
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311 | bool $safe = false |
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312 | ): string { |
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313 | if ($safe) { |
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314 | $text = strtr($text, "-_", "+/") . |
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315 | substr("===", (strlen($text) + 3) % 4); |
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316 | } |
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317 | |||
318 | return $this->decrypt( |
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319 | base64_decode($text), |
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320 | $key |
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321 | ); |
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322 | } |
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323 | |||
324 | /** |
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325 | * Encrypts a text. |
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326 | * |
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327 | * ```php |
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328 | * $encrypted = $crypt->encrypt( |
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329 | * "Top secret", |
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330 | * "T4\xb1\x8d\xa9\x98\x05\\\x8c\xbe\x1d\x07&[\x99\x18\xa4~Lc1\xbeW\xb3" |
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331 | * ); |
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332 | * ``` |
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333 | * |
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334 | * @param string $text |
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335 | * @param string|null $key |
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336 | * |
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337 | * @return string |
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338 | * @throws Exception |
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339 | */ |
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340 | public function encrypt(string $text, string $key = null): string |
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341 | { |
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342 | if (empty($key)) { |
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343 | $encryptKey = $this->key; |
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344 | } else { |
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345 | $encryptKey = $key; |
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346 | } |
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347 | |||
348 | if (empty($encryptKey)) { |
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349 | throw new Exception("Encryption key cannot be empty"); |
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350 | } |
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351 | |||
352 | $cipher = $this->cipher; |
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353 | $mode = strtolower( |
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354 | substr( |
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355 | $cipher, |
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356 | strrpos($cipher, "-") - strlen($cipher) |
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357 | ) |
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358 | ); |
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359 | |||
360 | $this->assertCipherIsAvailable($cipher); |
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361 | |||
362 | $ivLength = $this->ivLength; |
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363 | |||
364 | if ($ivLength > 0) { |
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365 | $blockSize = $ivLength; |
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366 | } else { |
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367 | $blockSize = $this->getIvLength( |
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368 | str_ireplace( |
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369 | "-" . $mode, |
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370 | "", |
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371 | $cipher |
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372 | ) |
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373 | ); |
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374 | } |
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375 | |||
376 | $iv = openssl_random_pseudo_bytes($ivLength); |
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377 | $paddingType = $this->padding; |
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378 | |||
379 | if ($paddingType != 0 && ($mode == "-cbc" || $mode == "-ecb")) { |
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380 | $padded = $this->cryptPadText($text, $mode, $blockSize, $paddingType); |
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381 | } else { |
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382 | $padded = $text; |
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383 | } |
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384 | |||
385 | /** |
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386 | * If the mode is "gcm" or "ccm" and auth data has been passed call it |
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387 | * with that data |
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388 | */ |
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389 | if (("-gcm" === $mode || "-ccm" === $mode) && !empty($this->authData)) { |
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390 | $authData = $this->authData; |
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391 | $authTag = $this->authTag; |
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392 | $authTagLength = $this->authTagLength; |
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393 | |||
394 | $encrypted = openssl_encrypt( |
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395 | $padded, |
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396 | $cipher, |
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397 | $encryptKey, |
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398 | OPENSSL_RAW_DATA, |
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399 | $iv, |
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400 | $authTag, |
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401 | $authData, |
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402 | $authTagLength |
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403 | ); |
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404 | |||
405 | $this->authTag = $authTag; |
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406 | } else { |
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407 | $encrypted = openssl_encrypt( |
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408 | $padded, |
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409 | $cipher, |
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410 | $encryptKey, |
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411 | OPENSSL_RAW_DATA, |
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412 | $iv |
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413 | ); |
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414 | } |
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415 | |||
416 | if ($this->useSigning) { |
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417 | $hashAlgo = $this->getHashAlgo(); |
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418 | $digest = hash_hmac($hashAlgo, $padded, $encryptKey, true); |
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419 | |||
420 | return $iv . $digest . $encrypted; |
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421 | } |
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422 | |||
423 | return $iv . $encrypted; |
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424 | } |
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425 | |||
426 | /** |
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427 | * Encrypts a text returning the result as a base64 string. |
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428 | * |
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429 | * @param string $text |
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430 | * @param mixed|null $key |
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431 | * @param bool $safe |
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432 | * |
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433 | * @return string |
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434 | * @throws Exception |
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435 | */ |
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436 | public function encryptBase64( |
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437 | string $text, |
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438 | $key = null, |
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439 | bool $safe = false |
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440 | ): string { |
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441 | if ($safe == true) { |
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442 | return rtrim( |
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443 | strtr( |
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444 | base64_encode( |
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445 | $this->encrypt($text, $key) |
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446 | ), |
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447 | "+/", |
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448 | "-_" |
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449 | ), |
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450 | "=" |
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451 | ); |
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452 | } |
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453 | |||
454 | return base64_encode( |
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455 | $this->encrypt($text, $key) |
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456 | ); |
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457 | } |
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458 | |||
459 | /** |
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460 | * Returns a list of available ciphers. |
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461 | * |
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462 | * @return array |
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463 | * @throws Exception |
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464 | */ |
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465 | public function getAvailableCiphers(): array |
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466 | { |
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467 | $availableCiphers = $this->availableCiphers; |
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468 | |||
469 | if (is_array($availableCiphers)) { |
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470 | $this->initializeAvailableCiphers(); |
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471 | |||
472 | $availableCiphers = $this->availableCiphers; |
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473 | } |
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474 | |||
475 | $allowedCiphers = []; |
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476 | foreach ($availableCiphers as $cipher) { |
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477 | if ( |
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478 | !( |
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479 | Str::endsWith(strtolower($cipher), "des") || |
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480 | Str::endsWith(strtolower($cipher), "rc2") || |
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481 | Str::endsWith(strtolower($cipher), "rc4") || |
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482 | Str::endsWith(strtolower($cipher), "des") || |
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483 | Str::endsWith(strtolower($cipher), "ecb") |
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484 | ) |
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485 | ) { |
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486 | $allowedCiphers[] = $cipher; |
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487 | } |
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488 | } |
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489 | |||
490 | return $allowedCiphers; |
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491 | } |
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492 | |||
493 | /** |
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494 | * Return a list of registered hashing algorithms suitable for hash_hmac. |
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495 | */ |
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496 | public function getAvailableHashAlgos(): array |
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497 | { |
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498 | if (function_exists("hash_hmac_algos")) { |
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499 | return hash_hmac_algos(); |
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500 | } |
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501 | |||
502 | return hash_algos(); |
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503 | } |
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504 | |||
505 | /** |
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506 | * @return string |
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507 | */ |
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508 | public function getAuthData(): string |
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509 | { |
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510 | return $this->authData; |
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511 | } |
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512 | |||
513 | /** |
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514 | * @return string |
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515 | */ |
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516 | public function getAuthTag(): string |
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517 | { |
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518 | return $this->authTag; |
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519 | } |
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520 | |||
521 | /** |
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522 | * @return int |
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523 | */ |
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524 | public function getAuthTagLength(): int |
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525 | { |
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526 | return $this->authTagLength; |
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527 | } |
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528 | |||
529 | /** |
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530 | * Returns the current cipher |
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531 | */ |
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532 | public function getCipher(): string |
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533 | { |
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534 | return $this->cipher; |
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535 | } |
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536 | |||
537 | /** |
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538 | * Get the name of hashing algorithm. |
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539 | */ |
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540 | public function getHashAlgo(): string |
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541 | { |
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542 | return $this->hashAlgo; |
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543 | } |
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544 | |||
545 | /** |
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546 | * Returns the encryption key |
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547 | */ |
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548 | public function getKey(): string |
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549 | { |
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550 | return $this->key; |
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551 | } |
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552 | |||
553 | /** |
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554 | * @param string $data |
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555 | * |
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556 | * @return CryptInterface |
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557 | */ |
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558 | public function setAuthData(string $data): CryptInterface |
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559 | { |
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560 | $this->authData = $data; |
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561 | |||
562 | return $this; |
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563 | } |
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564 | |||
565 | /** |
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566 | * @param string $tag |
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567 | * |
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568 | * @return CryptInterface |
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569 | */ |
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570 | public function setAuthTag(string $tag): CryptInterface |
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571 | { |
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572 | $this->authTag = $tag; |
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573 | |||
574 | return $this; |
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575 | } |
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576 | |||
577 | /** |
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578 | * @param int $length |
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579 | * |
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580 | * @return CryptInterface |
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581 | */ |
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582 | public function setAuthTagLength(int $length): CryptInterface |
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583 | { |
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584 | $this->authTagLength = $length; |
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585 | |||
586 | return $this; |
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587 | } |
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588 | |||
589 | /** |
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590 | * Sets the cipher algorithm for data encryption and decryption. |
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591 | * |
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592 | * The `aes-256-gcm' is the preferable cipher, but it is not usable |
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593 | * until the openssl library is upgraded, which is available in PHP 7.1. |
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594 | * |
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595 | * The `aes-256-ctr' is arguably the best choice for cipher |
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596 | * algorithm for current openssl library version. |
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597 | * |
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598 | * @param string $cipher |
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599 | * |
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600 | * @return CryptInterface |
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601 | * @throws Exception |
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602 | */ |
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603 | public function setCipher(string $cipher): CryptInterface |
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604 | { |
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605 | $this->assertCipherIsAvailable($cipher); |
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606 | |||
607 | $this->ivLength = $this->getIvLength($cipher); |
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608 | $this->cipher = $cipher; |
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609 | |||
610 | return $this; |
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611 | } |
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612 | |||
613 | /** |
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614 | * Set the name of hashing algorithm. |
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615 | * |
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616 | * @param string $hashAlgo |
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617 | * |
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618 | * @return CryptInterface |
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619 | * @throws Exception |
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620 | */ |
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621 | public function setHashAlgo(string $hashAlgo): CryptInterface |
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622 | { |
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623 | $this->assertHashAlgorithmAvailable($hashAlgo); |
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624 | |||
625 | $this->hashAlgo = $hashAlgo; |
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626 | |||
627 | return $this; |
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628 | } |
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629 | |||
630 | /** |
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631 | * Sets the encryption key. |
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632 | * |
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633 | * The `$key' should have been previously generated in a cryptographically |
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634 | * safe way. |
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635 | * |
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636 | * Bad key: |
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637 | * "le password" |
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638 | * |
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639 | * Better (but still unsafe): |
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640 | * "#1dj8$=dp?.ak//j1V$~%*0X" |
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641 | * |
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642 | * Good key: |
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643 | * "T4\xb1\x8d\xa9\x98\x05\\\x8c\xbe\x1d\x07&[\x99\x18\xa4~Lc1\xbeW\xb3" |
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644 | * |
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645 | * @param string $key |
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646 | * |
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647 | * @return CryptInterface |
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648 | */ |
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649 | public function setKey(string $key): CryptInterface |
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650 | { |
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651 | $this->key = $key; |
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652 | |||
653 | return $this; |
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654 | } |
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655 | |||
656 | /** |
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657 | * Changes the padding scheme used. |
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658 | * |
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659 | * @param int $scheme |
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660 | * |
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661 | * @return CryptInterface |
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662 | */ |
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663 | public function setPadding(int $scheme): CryptInterface |
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664 | { |
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665 | $this->padding = $scheme; |
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666 | |||
667 | return $this; |
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668 | } |
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669 | |||
670 | /** |
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671 | * Sets if the calculating message digest must used. |
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672 | * |
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673 | * @param bool $useSigning |
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674 | * |
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675 | * @return CryptInterface |
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676 | */ |
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677 | public function useSigning(bool $useSigning): CryptInterface |
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678 | { |
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679 | $this->useSigning = $useSigning; |
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680 | |||
681 | return $this; |
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682 | } |
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683 | |||
684 | /** |
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685 | * Assert the cipher is available. |
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686 | * |
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687 | * @param string $cipher |
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688 | * |
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689 | * @throws Exception |
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690 | */ |
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691 | protected function assertCipherIsAvailable(string $cipher): void |
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692 | { |
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693 | $availableCiphers = $this->getAvailableCiphers(); |
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694 | |||
695 | if (!in_array(strtoupper($cipher), $availableCiphers)) { |
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696 | throw new Exception( |
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697 | sprintf( |
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698 | "The cipher algorithm \"%s\" is not supported on this system.", |
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699 | $cipher |
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700 | ) |
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701 | ); |
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702 | } |
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703 | } |
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704 | |||
705 | /** |
||
706 | * Assert the hash algorithm is available. |
||
707 | * |
||
708 | * @param string $hashAlgo |
||
709 | * |
||
710 | * @throws Exception |
||
711 | */ |
||
712 | protected function assertHashAlgorithmAvailable(string $hashAlgo): void |
||
721 | ) |
||
722 | ); |
||
723 | } |
||
724 | } |
||
725 | |||
726 | /** |
||
727 | * Pads texts before encryption. |
||
728 | * |
||
729 | * @see http://www.di-mgt.com.au/cryptopad.html |
||
730 | * |
||
731 | * @param string $text |
||
732 | * @param string $mode |
||
733 | * @param int $blockSize |
||
734 | * @param int $paddingType |
||
735 | * |
||
736 | * @return string |
||
737 | * @throws Exception |
||
738 | */ |
||
739 | protected function cryptPadText( |
||
740 | string $text, |
||
741 | string $mode, |
||
742 | int $blockSize, |
||
743 | int $paddingType |
||
744 | ): string { |
||
745 | |||
746 | $paddingSize = 0; |
||
747 | $padding = null; |
||
748 | |||
749 | if ($mode == "cbc" || $mode == "ecb") { |
||
750 | $paddingSize = $blockSize - (strlen($text) % $blockSize); |
||
751 | |||
752 | if ($paddingSize >= 256) { |
||
753 | throw new Exception("Block size is bigger than 256"); |
||
754 | } |
||
755 | |||
756 | switch ($paddingType) { |
||
757 | case self::PADDING_ANSI_X_923: |
||
758 | $padding = str_repeat(chr(0), $paddingSize - 1) . chr($paddingSize); |
||
759 | break; |
||
760 | |||
761 | case self::PADDING_PKCS7: |
||
762 | $padding = str_repeat(chr($paddingSize), $paddingSize); |
||
763 | break; |
||
764 | |||
765 | case self::PADDING_ISO_10126: |
||
766 | $padding = ""; |
||
767 | |||
768 | foreach (range(0, $paddingSize - 2) as $counter) { |
||
769 | $padding .= chr(rand()); |
||
770 | } |
||
771 | |||
772 | $padding .= chr($paddingSize); |
||
773 | |||
774 | break; |
||
775 | |||
776 | case self::PADDING_ISO_IEC_7816_4: |
||
777 | $padding = chr(0x80) . str_repeat(chr(0), $paddingSize - 1); |
||
778 | break; |
||
779 | |||
780 | case self::PADDING_ZERO: |
||
781 | $padding = str_repeat(chr(0), $paddingSize); |
||
782 | break; |
||
783 | |||
784 | case self::PADDING_SPACE: |
||
785 | $padding = str_repeat(" ", $paddingSize); |
||
786 | break; |
||
787 | |||
788 | default: |
||
789 | $paddingSize = 0; |
||
790 | break; |
||
791 | } |
||
792 | } |
||
793 | |||
794 | if (!$paddingSize) { |
||
795 | return $text; |
||
796 | } |
||
797 | |||
798 | if ($paddingSize > $blockSize) { |
||
799 | throw new Exception("Invalid padding size"); |
||
800 | } |
||
801 | |||
802 | return $text . substr($padding, 0, $paddingSize); |
||
803 | } |
||
804 | |||
805 | /** |
||
806 | * Removes a padding from a text. |
||
807 | * |
||
808 | * If the function detects that the text was not padded, it will return it |
||
809 | * unmodified. |
||
810 | * |
||
811 | * @param string $text |
||
812 | * @param string $mode |
||
813 | * @param int $blockSize |
||
814 | * @param int $paddingType |
||
815 | * |
||
816 | * @return false|string |
||
817 | */ |
||
818 | protected function cryptUnpadText( |
||
819 | string $text, |
||
820 | string $mode, |
||
821 | int $blockSize, |
||
822 | int $paddingType |
||
823 | ) { |
||
824 | $paddingSize = 0; |
||
825 | $length = strlen($text); |
||
826 | |||
827 | if ( |
||
828 | $length > 0 && |
||
829 | ($length % $blockSize == 0) && |
||
830 | ($mode == "cbc" || $mode == "ecb") |
||
831 | ) { |
||
832 | switch ($paddingType) { |
||
833 | case self::PADDING_ANSI_X_923: |
||
834 | $last = substr($text, $length - 1, 1); |
||
835 | $ord = (int) ord($last); |
||
836 | |||
837 | if ($ord <= $blockSize) { |
||
838 | $paddingSize = $ord; |
||
839 | $padding = str_repeat(chr(0), $paddingSize - 1) . $last; |
||
840 | |||
841 | if (substr($text, $length - $paddingSize) != $padding) { |
||
842 | $paddingSize = 0; |
||
843 | } |
||
844 | } |
||
845 | |||
846 | break; |
||
847 | |||
848 | case self::PADDING_PKCS7: |
||
849 | $last = substr($text, $length - 1, 1); |
||
850 | $ord = (int) ord($last); |
||
851 | |||
852 | if ($ord <= $blockSize) { |
||
853 | $paddingSize = $ord; |
||
854 | $padding = str_repeat(chr($paddingSize), $paddingSize); |
||
855 | |||
856 | if (substr($text, $length - $paddingSize) != $padding) { |
||
857 | $paddingSize = 0; |
||
858 | } |
||
859 | } |
||
860 | |||
861 | break; |
||
862 | |||
863 | case self::PADDING_ISO_10126: |
||
864 | $last = substr($text, $length - 1, 1); |
||
865 | $paddingSize = (int) ord($last); |
||
866 | break; |
||
867 | |||
868 | case self::PADDING_ISO_IEC_7816_4: |
||
869 | $i = $length - 1; |
||
870 | |||
871 | while ($i > 0 && $text[$i] == 0x00 && $paddingSize < $blockSize) { |
||
872 | $paddingSize++; |
||
873 | $i--; |
||
874 | } |
||
875 | |||
876 | if ($text[$i] == 0x80) { |
||
877 | $paddingSize++; |
||
878 | } else { |
||
879 | $paddingSize = 0; |
||
880 | } |
||
881 | |||
882 | break; |
||
883 | |||
884 | case self::PADDING_ZERO: |
||
885 | $i = $length - 1; |
||
886 | |||
887 | while ($i >= 0 && $text[$i] == 0x00 && $paddingSize <= $blockSize) { |
||
888 | $paddingSize++; |
||
889 | $i--; |
||
890 | } |
||
891 | |||
892 | break; |
||
893 | |||
894 | case self::PADDING_SPACE: |
||
895 | $i = $length - 1; |
||
896 | |||
897 | while ($i >= 0 && $text[$i] == 0x20 && $paddingSize <= $blockSize) { |
||
898 | $paddingSize++; |
||
899 | $i--; |
||
900 | } |
||
901 | |||
902 | break; |
||
903 | |||
904 | default: |
||
905 | break; |
||
906 | } |
||
907 | |||
908 | if ($paddingSize && $paddingSize <= $blockSize) { |
||
909 | if ($paddingSize < $length) { |
||
910 | return substr($text, 0, $length - $paddingSize); |
||
911 | } |
||
912 | |||
913 | return ""; |
||
914 | } else { |
||
915 | $paddingSize = 0; |
||
916 | } |
||
917 | } |
||
918 | |||
919 | if (!$paddingSize) { |
||
920 | return $text; |
||
921 | } |
||
922 | } |
||
923 | |||
924 | /** |
||
925 | * Initialize available cipher algorithms. |
||
926 | * |
||
927 | * @param string $cipher |
||
928 | * |
||
929 | * @return int |
||
930 | * @throws Exception |
||
931 | */ |
||
932 | protected function getIvLength(string $cipher): int |
||
939 | } |
||
940 | |||
941 | /** |
||
942 | * Initialize available cipher algorithms. |
||
943 | * |
||
944 | * @throws Exception |
||
945 | */ |
||
946 | protected function initializeAvailableCiphers(): void |
||
947 | { |
||
948 | if (!function_exists("openssl_get_cipher_methods")) { |
||
959 | } |
||
960 | } |
||
961 |
Let?s assume that you have a directory layout like this:
and let?s assume the following content of
Bar.php
:If both files
OtherDir/Foo.php
andSomeDir/Foo.php
are loaded in the same runtime, you will see a PHP error such as the following:PHP Fatal error: Cannot use SomeDir\Foo as Foo because the name is already in use in OtherDir/Foo.php
However, as
OtherDir/Foo.php
does not necessarily have to be loaded and the error is only triggered if it is loaded beforeOtherDir/Bar.php
, this problem might go unnoticed for a while. In order to prevent this error from surfacing, you must import the namespace with a different alias: